Sheet stack folding machine



2 Sheets-Sheet 1 Filed Feb. 17, 1965 Jan. 10, 1967 J. KUNZ SHEET STACKFOLDING MACHINE 2 Sheets-Sheet 2 Filed Feb. 17. 1965 United StatesPatent 3,297,315 SHEET STACK FOLDING MACHINE Jakob Kunz, Zurich,Switzerland, assignor to Tages- Anzeiger fur Stadt und Kanton ZurichA.-G., Zurich, Switzerland Filed Feb. 17, 1965, Ser. No. 433,302 Claimspriority, application Switzerland, Feb. 20, 1964,

2,031/ 64 19 Claims. (Cl. 270-86) The present invention has reference toan improved folding machine for the folding of stacks of sheets, pages,or like articleshereinafter referred to simply. as stacks ofsheetsparticularly newspapers, periodicals or the like.

A primary object of the present invention contemplates the provision ofan improved folding machine which enables continuous, rapid andreliable. folding of relatively thick stacks of sheets.

Another important object of the present invention relates to an improvedconstruction of folding machine for the folding of stacks of sheets orsimilar articles in a highly reliable and efiicient manner, the machinefor carrying out such operation is of relatively simple and economicalconstruction, easy to operate and service, and not readily subject tomalfunctions.

Still a further important object of the present invention has referenceto an improved folding machine for the folding of stacks of sheets orthe like, incorporating means for continuously feeding individual stacksof such sheets through the machine, means for folding the stack ofsheets, and means for applying an additional force for furtherpressingtogether the folded stack of sheets after the latter has left theconveying means.

Yet a further very considerable object. of the present invention is toprovide an improved folding machine for the folding of stacks of sheetsor the like incorporating means which safeguard against jamming of themachine in the event that two such stacks of sheets are simultaneouslyconveyed between at least one pair of fold rollers.

In order to implement these and still further objects of the inventionwhich will become more readily appa rent as the description of apreferred embodiment is undertaken, it will be appreciated that in thefirst instance the inventive folding maclu'ne, according to one veryimportant aspect thereof, contemplates the provision of at least twoendless driven members, specifically belts, for instance, for fixedlyclamping the stacks of sheets at their folding region or location, asWell as the provision of guide or deflector elements for the folding ofthe stack of sheets about one of the belts during such time as suchstack of sheets is entrained and conveyed by the aforementioned two beltmembers.

Advantageously, the belt member about which the stacks of sheets arefolded travels upon a row of fixedly mounted rollers. A second beltmember travels over a row of roller mounted in a displaceable support orcarrier member which is adjustable with respect to the first mentionedrow of rollers. In so doing, in the depicted embodiment the first beltmember about which the stack of pages or sheets are folded, isadvantageously substantially circular in cross-section and the' secondbelt member possesses a substantially wedge-shaped crosssectionalconfiguration.

It is further advantageous if at least one pair of rollers are arrangedafter the endless belt members and guide elements. This pair of rollersserves the purpose of additionally pressing together the folded stack ofsheets after leaving the aforesaid belt members. According to apreferred constructional manifestation two pairs of rollers are arrangedbehind one another, the rearmost pair in ICC the zone of the fold lineof the stack of sheets each possessing a stepped portion of largerdiameter, in order to exert an increased terminal pressure at the foldlocation or line. Furthermore, the rollers of both pairs of rollers canbe variably biased or loaded so that they selectively exert a greater orlesser folding force, whereby the adjustment means for such purpose areconstructed in such manner that the rollers of both pairs of rollers canbe selectively regulated such that both pairs of rollers aresubstantially similarly loaded to exert substantially the same foldingeffect upon the stacks of sheets, or that one pair of rollers exerts asmaller fold force and the other pair a larger foldforce. In order toattain a safety measure for the situation that unintentionally twostacks of sheets simultaneously arrive between the rollers safety orprotection springs can act upon the rollers of the pair of rollers,whereby in the presence of undue pressure these rollers can effectivelyspread apart while compressing such springs, thereby preventing damageto the folding machine. Further, it is advantageous if the guide ordeflector elements are formed from rods bent along the path of foldingfor the stacks of sheets in the manner of a substantially screw orhelical line.

Other features, objects and advantages of the present invention willbecome apparent by reference to the following detailed description anddrawings in which:

FIGURE 1 schematically illustrates a longitudinal sectional view througha preferred embodiment of inventive folding machine;

FIGURE 2 is a fragmentary cross-sectional view of the folding machine ofFIGURE 1, taken along the line II II thereof;

FIGURE 3 is a top plan view of the folding machine of FIGURE 1;

FIGURE 4 is a horizontal cross-sectional view through the mountingarrangement for the pairs of additional fold rollers, further showingdetails of the adjusting means therefor;

FIGURE 5 is a cross-sectional view, similar to FIG- URE 4, with theaforementioned rollers under different loading and, therefore, shown ina different position; and.

FIGURE 6 schematically illustrates a view through a folded stack ofsheets, depicting details of a portion of the rear pair of fold rollers.

Describing now the drawings, the illustrated folding machine M embodiesa supporting frame 1 at which there is mounted a lower row or set ofcarrier or support rollers 2. An endless belt member 3, which in theillustrated embodiment possesses a substantially circular cross-section,travels over the aforementioned row of support rollers 2. Furthermore,the belt member 3 is guided over deflecting rollers 4 and a drive roller5. It will also be observed that a further set or row of upper supportor carrier rollers 6 is mounted at a support rail 7 or the like. Largerdeflecting rollers 8 are mounted at both ends of this support rail 7.Once again, an endless V-belt 9 shown to be of substantiallywedge-shaped crosssection travels over the support rollers 6 anddeflecting rollers 8. Hence, the sets of rollers 2 and 6 and theirassociated belts 3 and 9 respectively, provide means for fixedlyclamping and continually conveying a stack of sheets 60 through theinventive folding machine M.

Considering further physical structure of the support or carrier rail 7it will be seen that such is suspended at two threaded rods or shafts1t] rotatably mounted in brackets or arms 11. These shafts 10 arecapable of being actuated by hand-operated wheels 12 in order toelevationally displace the aforesaid support rail 7, to thereby regulatethe spacing of the V-belt member 9 from the belt member 3.

By referring to FIGURE 3 it will be seen that a drive pulley or roller13 is seated upon a shaft 8a of the lefthand deflecting roller 8.Moreover, a drive belt member 14 is trained about this drive pulley 13and, additionally, is guided over an intermediate pulley or roller 15rotatably mounted to the machine frame 1a. This intermediate pulley 15is driven by a belt 16 through the agency of a pulley or roller 17seated upon a shaft 18 which also drives the drive roller 5 by means ofa further belt member 19. A V-belt pulley disk 20 is seated upon theshaft 18, and is driven by a V-belt pulley disk 22 through the agency ofV-belt drive member 21. This pulley disk 22 is advantageously driven bya drive motor 23 with infinitely variable speed transmission. Drivemotor 23 and pulley disk 22 are conveniently arranged upon balance orrocker means 24, capable of being adjusted via a threaded spindle 25 inorder to maintain the V-belt member 21 in tensioned state.

A belt pulley 26 is driven from the shaft 18 through the agency of anon-illustrated miter-wheel gearing. The respective rotatable shaftmembers 29 of two pairs of additional fold or folding rollers 30, 31 and32, 33 are driven by this belt pulley 26 via belt 27 and pulleys 28. InFIGURE 6 there is shown that the rearmost pair of rollers 32, 33incorporates a respective stepped upper portion 32a and 33a which is oflarger diameter than the remaining body portion of the relevant rollers32, 33. The shafts 29 of these pairs of rollers 30, 31 and 32, 33 aremounted in journal boxes 34, 35, 36 and 37 respectively (FIGURE 4). Arespective angle lever or bell crank 38, 39, 40, 41, each of which isrockable about an associated pivot shaft 42 engages at one respectivearm 38a, 39a, 40a and 41a with the journal boxes 34, 35, 36 and 37respectively. The respective free arm 38b and 39b of both angle levers38 and 39 respectively,-bears against a disk member 43 displaceablyarranged upon a threaded bushing or socket 44. This threaded bushing 44is seated upon a threaded portion 45 of a threaded spindle 46.Additionally, a sleeve member 70 provided with a groove or recess 71 forreceiving the arms 38b and 39b is seated upon the bushing 44 andprevents rotation of the latter relative to threaded spindle 46.

A pressure spring 48 providing a safety mechanism, as will be furtherexplained hereinafter, is located between the plate or disk member 43and afurther plate or disk member 47 rigidly mounted to the threadedbushing 44. In analogous manner, the respective free arms 40b and 41b ofboth angle levers 40 and 41 respectively, bear against a plate or diskmember 49 displaceably arranged upon a further threaded bushing 50. Thelatter is seated upon a threaded portion 51 of the threaded spindle 46.Here again, a pressure spring 53, also providing a safety mechanism, isdisposed between the disk member 49 and a further disk member 52 rigidlymounted upon the threaded bushing 50. Moreover, a further sleeve member72 likewise provided with a groove or recess 73 for receiving the arms40b and 41b is seated upon the bushing and prevents rotation of thelatter, relative to threaded spindle 46.

This threaded spindle 46 is rotatably and displaceably mounted at itsleft end in a frame portion 54 and at its right end piercingly extendsthrough a threaded bushing 55 rotatably mounted in a supporting frame56. The bushing 55 possesses a hexagonal portion 57 which can be rotatedby an appropriate tool member or key. Naturally, in lieu of thehexagonal portion 57 the threaded bushing 55 can also possess a toothconstruction, so that it can be rotated by a transmission gear forinstance. Further, the left end of the threaded spindle 46 possesses asquare portion 58 which can cooperate with an appropriate key orhand-wheel for the purpose of rotating the aforesaid threaded spindle46.

Due to the a-foredescribed construction of the adjustment means when thethreaded spindle 46 is rotated in one or the other direction by means ofthe square portion 46 then, due to the opposite pitch of the threadedportions 45 and 51, the fixedly mounted disks 47 and 52 respectively,are either advanced towards one another or away from one another inconsequence of a corresponding axial shifting of the associated threadedbushings 44 and 50 respectively. As a result, the bias on the springs 48and 53 is either reduced or increased, so that both of the pairs ofrollers 30, 31 and 32, 33 which are correspondingly loaded or biased,can either be more easily moved away from one another .and, thus, exerta smaller folding force, or else have to be exposed to a large force inorder to be displaced away from one another and, thus, exert a greaterfolding force. On the other hand, if the threaded bushing 55 is rotatedin one or the other direction, then it is possible to individually andin opposite sense adjust the action of each pair of rollers 30, 31 and32, 33 since, the spindle or shaft 46 can be displaced to the right orleft of FIGURE 4. Assuming that the hexagonal portion 57 is turned suchas to displace the threaded spindle 46 to the right in the direction ofarrow D of FIGURES 4 and 5, then the bushing 44 and fixedly supporteddisk 47 as well as the bushing 50 and its fixedly supported disk 52 arelikewise displaced in the direction of arrow D. Consequently, the spring48 is relaxed while the spring 53 is further stressed, with the resultthat the pair of rollers 30, 31 are less loaded and the other pair ofrollers 32, 33 more strongly loaded. Consequently, rollers 30, 31 exerta smaller folding .force and rollers 32, 33 a greater one. Manipulationof the hexagonal portion 57 so as to displace the threaded spindle 46opposite the direction of arrow D obviously etfectuates a reverseadjustment of the respective pairs of rollers 30, 31 and 32, 33.

Finally, by inspecting FIGURES 2 and 3 it will be recognized that guideor reffector rods 59 which bring about a bending of the stack of sheets60 about the belt member 3 are connected with the machine frame In. Itshould be understood that these guide rods 59 lie in one substantiallyhorizontal plane ZZ at their left end (FIGURE 3), are flexed along thepath of folding for the sheets 60 in helical or screw lineconfiguration, and terminate at their right end in two substantiallyvertical planes, schematically indicated in FIGURE 3 by lines XX and YY,respectively.

The manner of operation of the described folding ma- I chine is asfollows and will no be explicitly considered:

Flat stacks of sheets 60 or the like, such as typically encountered inthe newspaper art for instance, are delivered to the inventive foldingmachine M such that the regions R of such stack of sheets 60 which areto be folded arrive between both of the belt members 3 and 9 whichsuccessively seize and fixedly clamp such stacks of sheets 60 at theaforesaid fold region R. Due to revolving of the belt members 3 and 9the stacks of sheets 60 are entrained from the left to the right of thefolding machine M. During this time the guide or deflector rods 59 actfrom above upon the stacks of sheets 60 in such a manner as to graduallybend these from the flat position A (FIGURE 2), in the direction of thearrow E, about the belt member 3 into the position B shown in full linesand, thereafter, are folded at the ends 59a of the guide rods 59 intothe folded position C.

Upon leaving the conveying belt members 3 and 9 the now folded stack ofsheets 60 are further passed between the pairs of rollers 30, 31 and 32,33 whereby the folded stack of sheets 60 are pressed together such as tothereafter be folded so strongly that they do not of themselves tend toopen. Depending upon the thickness'of the stack of sheets 60 it ispossible to regulate the position of the support or carrier rail 7 bymeans of the hand-operated wheels 12. Further, it should be recalledthat the pairs of rollers 30, 31 and 32, 33 can be selectively loaded orbiased. For instance, and as was explained, by rotating the threadedspindle 46 via the square portion 58 the rollers of both roller pairscan be substantially similarly biased or loaded via the springs 48, 53in the same sense and by virtue of the opposite pitch of the threadedportions 45 and 51, whereas by rotating the threaded bushing 55 therollers of both aforesaid roller pairs 30, 31 and 32, 33 can be loadedor biased in opposite sense with respect to one another in order toadjust their folding action upon the folded stack of sheets 60. I

As best realized by inspecting FIGURE 6, the stack of sheets 60 areadditionally pressed together at their fold line or region R by means ofthe stepped roller portions 32a and 33a of the rearmost or downstreampair of rollers 32, 33. This is done in order to positively safeguardagainst a subsequent opening of the folded stack of sheets 60. Moreover,as previously explained the springs 48 and 53 provide a safety means inthe event that two stacks of sheets should simultaneouslyunintentionally arrive between the mentioned pairs of rollers 30, 31 and32, 33 since these springs will yield under the force of such sheets toenable these rollers to move apart, and, therefore, prevent damage tothe folding machine.

While there is shown and described a present preferred embodiment of theinvention it is to be distinctly understood that the invention is notlimited thereto but may be otherwise variously embodied and practicedwithin the scope of the following claims.

What is claimed is:

1. A folding machine for folding stacks of sheets, particularlynewspapers, comprising at least two endless, driven belt members forfixedly clamping the stack of sheets to be folded at their region to befolded, and guide elements positioned to fold said stack of sheets aboutone of said belt members during such time as said stack of sheets areentrained by said two belt members, a row of stationarily mountedrollers over which travels said one belt member about which said stackof sheets are folded, a further row of rollers cooperating with said rowof stationarily mounted rollers, support means mounted to bedisplaceable with respect to said row of stationarily mounted rollers,said further row of rollers being carried by said support means, theother of said belt members being trained about said further row ofrollers.

2. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 1 wherein said one belt member possessesa substantially circular crosssectional configuration, said other beltmember possess- 1ng a substantially wedge-shaped cross-sectionalconfiguration.

3. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 1 further including at least one pair ofrollers arranged after said endless belt members and said guide elementsin the direction of travel of said stack of sheets for additionallypressing together said stack of sheets after the latter has departedfrom between said belt members.

4. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 3 including two pairs of rollers arrangedbehind one another in the di rection of travel of said stack of sheetsfor additionally pressing together said stack of sheets after the latterhas departed from between said belt members, the rearmost pair ofrollers each including a stepped portion of larger diameter than theremainder of the corresponding roller, said stepped portion of eachroller of said rearmost pair of rollers being arranged in the foldingzone for said stack of sheets in order to exert an increased terminalpressure at said region of said stack of sheets to be folded.

5. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 4 further including adjustment means forregulating said two pairs of rollers such that each pair of rollersexerts substantially the same folding force upon said stack of sheets.

6. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 5 wherein said adjustment means includemeans for selectively regulating each pair of rollers such that one pairof rollers exerts a greater folding force than the other pair of rollersupon said stack of sheets.

7. A folding machine for "folding stacks of sheets, particularlynewspapers, according to claim 3 including protective spring meanseffective at said pair of rollers for protecting the rollers againstundue forces exerted by said stack of sheets.

8. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 1, wherein said guide elements compriserod members which are bent in substantially screw-line configurationalong the path of folding for said stack of sheets.

9. A fol-ding machine for folding stacks of sheets, particularlynewspapers, comprising a first row of stationarily mounted rollers, asecond row of rollers positioned to cooperate with said first row ofrollers, support means for carrying said second row of rollers, saidsupport means being mounted to be displaceable with respect to saidfirst row of rollers in order to vary the spacing between said first andsecond row of rollers to accommodate for different thicknesses of thestacks of sheets, a respective belt member trained about each row ofrollers, drive means for revolving said belt members in order to feedthe stacks of sheets when disposed between said first and second row ofrollers, and means positioned to fold said stacks of sheets locatedbetween said first and second row of rollers about the belt membertrained about said first row of rollers.

10. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 9 wherein said belt member trained aboutsaid first row of rollers possesses a substantially circularcross-sectional configuration.

11. A folding machine for folding stacks of sheets, particularlynewspapers, comprising a first set of stationarily mounted rollers, asecond set of rollers positioned to cooperate with said first set ofrollers, support means for carrying said second set of rollers, saidsupport means being mounted to be displaoeable with respect to saidfirst set of rollers in order to vary the spacing between said first andsecond set of rollers to accommodate for different thicknesses of thestacks of sheets, a respective belt member trained about each set ofrollers, drive means for revolving said belt members in order to feedthe stacks of sheets when disposed between said first and second set ofrollers along a folding path, means positioned at opposite sides of saidfirst and second set of rollers for folding said stacks of sheetspositioned between said first and second row of rollers about the beltmember trained about said first set of rollers, at least one pair offolding rollers arranged at the downstream side of said first and secondset of rollers along said folding path for exerting an additionalfolding force upon said stacks of sheets.

12. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 11 wherein said first and second set ofrollers include an inlet end and a discharge end for said stack ofsheets, said folding means incorporating individual rod members flexedalong a substantially helical line from said inlet end towards saiddischarge end, said rod members being disposed in substantially a singleplane at the region of said inlet end and at the region of saiddischarge end being disposed in two substantially parallel planeslocated to opposite sides of said first and second set of rollers.

13. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 11 wherein two pairs of folding rollersare arranged at the downstream side of said first and second set ofrollers along said folding path for exerting an additional folding forceupon said stack of sheets, and adjustment means for regulating thefolding action exerted upon said stack of sheets by each pair of foldingrollers.

14. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 13 wherein said adjustment meansincorporates mechanism for regulating each pair of folding rollers tocarry out substantially the same folding action upon said stack ofsheets and mechanism for regulating each pair of folding rollers tocarry out a different folding action upon said stack of sheets.

15. A folding machine for folding stacks of sheets,

particularly newspapers, according to claim 13 wherein said adjustmentmeans incorporates a threaded spindle having a respective threadedportion for each pair of folding rollers of opposite pitch, a threadedbushing mounted on each threaded portion and cooperating with anassociated pair of folding rollers, a respective first disk memberprovided for each threaded bushing and slidable therealong, a respectivesecond disk member fixedly connected to each threaded bushing, and arespective spring member disposed between each fixed and slidable diskmembers of each threaded bushing.

16. A folding machine "for folding stacks of sheets, particularlynewspapers, according to claim 15 wherein said adjustment means furtherincludes means enabling rotation of said threaded spindle to axiallyadvance said threaded 'bushings along said threaded spindle in oppositedirections so as to bias each of said spring members in the same sense,and means for axially displacing said threaded spindle in order to biassaid spring members in opposite sense.

17. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 16 wherein said respective second diskmembers confront one another.

18. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 17 further including lever means arrangedto cooperate with each roller of said two pairs of folding rollers andsaid respective spring members.

19. A folding machine for folding stacks of sheets, particularlynewspapers, according to claim 15 wherein said respective spring membersprovide safety means which compensate for undue forces exerted upon saidtwo pairs of folding rollers. 3

References Cited by the Examiner UNITED STATES PATENTS 331,281 12/1885Crowell 27086 589,083 8/1897 Hart 27086 3,127,165 3/1964 St. Denny et a1270-66 EUGENE R. CAPOZIO, Primary Examiner.

1. A FOLDING MACHINE FOR FOLDING STACKS OF SHEETS, PARTICULARLYNEWSPAPERS, COMPRISING AT LEAST TWO ENDLESS, DRIVEN BELT MEMBERS FORFIXEDLY CLAMPING THE STACK OF SHEETS TO BE FOLDED AT THEIR REGION TO BEFOLDED, AND GUIDE ELEMENTS POSITIONED TO FOLD SAID STACK OF SHEETS ABOUTONE OF SAID BELT MEMBERS DURING SUCH TIME AS SAID STACK OF SHEETS AREENTRAINED BY SAID TWO BELT MEMBERS, A ROW OF STATIONARILY MOUNTEDROLLERS OVER WHICH TRAVELS SAID ONE BELT MEMBER ABOUT WHICH SAID STACKOF SHEETS ARE FOLDED, A FURTHER ROW OF ROLLERS COOPERATING WITH SAID ROWOF STATIONARILY MOUNTED ROLLERS, SUPPORT MEANS MOUNTED TO BEDISPLACEABLE WITH RESPECT TO SAID ROW OF STATIONARILY MOUNTED ROLLERS,SAID FURTHER ROW OF ROLLERS BEING CARRIED BY SAID SUPPORT MEANS, THEOTHER OF SAID BELT MEMBERS BEING TRAINED ABOUT SAID FURTHER ROW OFROLLERS.